1. Field of the Invention
This invention relates to disk drive suspensions, and, more particularly, to modified load beams in disk drive suspensions that flex at a locus of articulation intermediate the beam rigid portion ends to maintain the pitch static attitude of the slider at the optimum small positive angle when the slider in out of operative contact with the disk and at the optimum 0xc2x0 when the slider is in operative contact with the disk. The term operative contact herein refers to the condition of the slider flying on the disk surface on a cushion of air in disk undulation following relation and does not include physical touching of the slider and disk surface.
2. Related Art
Disk drive use load beam to maintain the slider that carries the read write head in operative contact with the disk. Typically, the load beam through a spring portion exerts a force that brings the slider carried on the load beam rigid portion into a predetermined close spacing to the disk while the disk is spinning. When the disk is not spinning the slider is lifted away from the disk to a greater spacing. The slider must then be lowered when the disk spinning resumes.
Optimally, the slider when flying at the disk surface has a pitch angle that is 0xc2x0 to a reference datum so that the slider face and the disk are parallel to each other. When the slider is lifted to or from the disk or suspended above the disk it falls to an angle that is a function of the angle of the flexure tongue that holds the slider and the angle of the load beam rigid portion to which the flexure is attached.
In this invention, the angle of the suspended slider is maintained at a small positive angle such as 1xc2x0. In this context positive means that the slider nose or leading face is up relative to the trailing face such that initial (and last) contact of the slider with the disk surface is by the lower trailing face edge and not the leading face edge.
In the prior art the effort to have the positive angle for load and unload has had to be compromised with the simultaneous need to have a 0xc2x0 pitch angle during flying of the slider at the disk surface. In accordance with the invention, the previous compromises are no longer required.
It is an object of the invention, therefore, to provide an improved disk drive suspension. It is a further object to provide a modified load beam in a disk drive suspension that both supports the slider at a 0xc2x0 when flying but also maintains the slider at a small positive pitch angle during load and unload cycles.
These and other objects of the invention to become apparent hereinafter are realized in a disk drive suspension comprising a load beam and a flexure carrying a slider for contact or not with a disk, the load beam comprising a base portion, a rigid beam portion having rigidity-imparting left and right edge rails each comprising rearward, forward and intermediate rail sections, and a spring portion between the base and rigid beam portions, the rigid beam portion having rear ward, intermediate and forward beam sections corresponding to the rearward, forward and intermediate rail sections, respectively; the forward beam section extending the length of and mounting the flexure, the rearward beam section being attached to the spring portion, and the intermediate beam section having opposing left and right intermediate rail section discontinuities to reduce intermediate section rigidity there and form a locus of intermediate beam portion articulation rearward of the flexure, whereby the intermediate section flexes in response to slider contact or not with the disk to maintain the slider at a small positive pitch relative to the disk in the absence of disk operating contact and at a 0xc2x0 pitch when in disk operating contact under spring portion loading.
In a further embodiment, the invention provides a disk drive suspension comprising a load beam and a flexure carrying a slider for contact or not with a disk, the load beam comprising a base portion, a rigid beam portion having rigidity-imparting left and right edge rails comprising rearward, forward and intermediate rail sections, and a spring portion between the base and rigid beam portions, the rigid beam portion having rearward, intermediate and forward beam sections corresponding to the rearward, forward and intermediate rail sections, respectively; the forward beam section extending the length of and mounting the flexure, the rearward beam section being attached to the spring portion, and the intermediate beam section having a locus of articulation formed by opposing discontinuities in the left and right intermediate rail sections, and a stiffener plate attached to the rearward beam section in intermediate beam section overlying relation to block overcenter movement of the intermediate portion relative to the rearward portion in the unloaded condition of the suspension, whereby the intermediate section flexes in response to slider contact or not with the disk to maintain the slider at a small positive pitch relative to the disk in the absence of disk operating contact and at a 0xc2x0 pitch when in disk operating contact under spring portion loading.
In these and like embodiments, typically, the invention includes a mounting plate attached to the base portion, the rigid portion is of generally triangular shape, the edge rails converging toward the forward beam section, the load beam sections are formed on a single stainless steel web, and, the rail section discontinuities increase or decrease in width responsive to movement of the slider from or to the disk.